The Weekly 25 March 2012

Common names: Coulter's lupine, desert lupine, Mojave lupine, sand lupine, arroyo lupine. Alternate spelling for lupine is lupin, giving rise to pronunciation with a short “i”. Scientific name: sparsiflorus 1

TAV location: Widespread along Galileo and somewhat along Langtry. Nice clumps can be found right by the road at lot 80 and lot 188.

Discussion: I’ve been avoiding the lupines but decided to write this in honor of the ones we had to lose for the good of our roads. These really like growing in the little crack at roads’ edge.

Why was I avoiding lupines? I kept finding statements such as "The genus [Lupinus] is notoriously difficult because of lack of clear diagnostic features."2 Or this: “The of this genus is difficult, and authorities differ greatly in their interpretations…”.3 If someone wants to have a long discussion on Lupinus taxonomy, let me know. For now, I’ll tell you my conclusions and let you enjoy the flowers.

The most common lupine in the Village is Coulter’s lupine. The flowers are large and showy, blue- purple with a white spot that turns pink as flowers age (all white flowers are sometimes seen). The leaves of all lupines are palmately compound (compound – more than one leaflet on each leaf stalk, palmate – all leaflets attached to the leaf stalk at a single point, see photo lower right). The leaflets on Coulter’s lupine are narrow, about the same width for their entire length.

Coulter’s lupine is poisonous, especially the seeds. The local O’odham had no practical use for the plant but named it “sun-hand” for the sun-tracking habit of its leaves4 (photos to right). 2PM, leaves face up/south 9AM, leaves face east

I’ve seen bajada lupine (Lupinus concinnus) around the Village as well. It is a much smaller, but hairier, plant. The flower stalk barely rises above the leaves, not very showy. The flowers are pink and white. The leaflets are much wider at the tip than the base. I can’t find a definitive description of another local lupine, lupine (Lupinus arizonicus). My current thinking is that it is large and showy like Coulter’s lupine but has Flower and leaf comparison: pinker flowers and the leaflet shape of bajada lupine. I Coulter’s lupine on left, haven’t seen it at TAV. And then there’s the Texas bajada lupine on right. bluebonnet – more info at http://tinyurl.com/48lw8.

1 GRIN Online Database is the source of the currently accepted scientific name. Photo and text by Mary Welch-Keesey 2 Stanley Welsh quoted here: http://tinyurl.com/Welshquote 3 Arizona Flora, Thomas H. Kearney, et al. 1951. 4 A Natural History of the Sonoran Desert, ASDM, 2000.